From 675b37002e2625dee9de5976e982f7fb46377527 Mon Sep 17 00:00:00 2001
From: Heiko Reese <heiko.reese@kit.edu>
Date: Wed, 11 Aug 2021 01:45:30 +0200
Subject: [PATCH] =?UTF-8?q?=E2=80=A6?=
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---
 src/libexim-kitencrypt-dlfunc.c | 68 ++++++++++++++++++++++++++++-----
 1 file changed, 58 insertions(+), 10 deletions(-)

diff --git a/src/libexim-kitencrypt-dlfunc.c b/src/libexim-kitencrypt-dlfunc.c
index a541698..5d49607 100644
--- a/src/libexim-kitencrypt-dlfunc.c
+++ b/src/libexim-kitencrypt-dlfunc.c
@@ -9,13 +9,14 @@
 /* Exim4 dlfunc API header */
 #include <local_scan.h>
 
-int kitencrypt(uschar **yield, int argc, uschar *argv[]) {
-	int sinit;
+/*
+ * Encrypt first argument with fixed public key from recipient_pk.h
+ */
+int sodium_crypto_box_seal_kit(uschar **yield, int argc, uschar *argv[]) {
 	size_t messagelen;
 	unsigned char * message;
 
-	sinit = sodium_init();
-	if (sinit == -1 ) {
+	if (sodium_init() == -1 ) {
 		*yield = string_copy(US"Unable to initialize libsodium");
 		return ERROR;
 	}
@@ -26,7 +27,54 @@ int kitencrypt(uschar **yield, int argc, uschar *argv[]) {
 
 	// get cleartext message
 	message = argv[0];
-	messagelen = strlen(message);
+	messagelen = strlen((const char *) message);
+
+	// prepare buffer for ciphertext
+	unsigned int cipherlen = messagelen + crypto_box_SEALBYTES;
+	unsigned char * ciphertext = malloc(cipherlen);
+	sodium_memzero(ciphertext, cipherlen);
+
+	// encrypt message
+	crypto_box_seal(ciphertext, message, messagelen, recipient_pk);
+
+	// base64-encode the ciphertext
+	unsigned int outputsize = sodium_base64_ENCODED_LEN(cipherlen, sodium_base64_VARIANT_ORIGINAL);
+	unsigned char * outstring = malloc(outputsize);
+	sodium_memzero(outstring, outputsize);
+
+	sodium_bin2base64((char * const) outstring, outputsize,
+			ciphertext, cipherlen,
+			sodium_base64_VARIANT_ORIGINAL);
+	free(ciphertext);
+
+	// return base64-encoded ciphertext
+	*yield = string_copy(outstring);
+	free(outstring);
+
+	return OK;
+}
+
+/*
+ * Encrypt first argument with passworf from the second argument
+ */
+/*
+// https://libsodium.gitbook.io/doc/hashing/short-input_hashing
+int sodium_crypto_box_seal_password(uschar **yield, int argc, uschar *argv[]) {
+	size_t messagelen;
+	unsigned char * message;
+
+	if (sodium_init() == -1 ) {
+		*yield = string_copy(US"Unable to initialize libsodium");
+		return ERROR;
+	}
+	if (argc != 2) {
+		*yield = string_sprintf("Wrong number of arguments (got %i, expected 1)", argc);
+		return ERROR;
+	}
+
+	// get cleartext message
+	message = argv[0];
+	messagelen = strlen((const char *) message);
 
 	// prepare buffer for ciphertext
 	unsigned int cipherlen = messagelen + crypto_box_SEALBYTES;
@@ -37,19 +85,19 @@ int kitencrypt(uschar **yield, int argc, uschar *argv[]) {
 	crypto_box_seal(ciphertext, message, messagelen, recipient_pk);
 
 	// base64-encode the ciphertext
-	unsigned int outputsize = sodium_base64_ENCODED_LEN(cipherlen, sodium_base64_VARIANT_URLSAFE);
+	unsigned int outputsize = sodium_base64_ENCODED_LEN(cipherlen, sodium_base64_VARIANT_ORIGINAL);
 	unsigned char * outstring = malloc(outputsize);
 	explicit_bzero(outstring, outputsize);
 
-	sodium_bin2base64(outstring, outputsize,
+	sodium_bin2base64((char * const) outstring, outputsize,
 			ciphertext, cipherlen,
-			sodium_base64_VARIANT_URLSAFE);
-
+			sodium_base64_VARIANT_ORIGINAL);
 	free(ciphertext);
 
+	// return base64-encoded ciphertext
 	*yield = string_copy(outstring);
-
 	free(outstring);
 
 	return OK;
 }
+*/